Corner lock box



Sept. 25, 1956 B. KLEINGERS, JR

CORNER LOCK BOX Filed Dec. 15, 1955 IN VEN TOR. fllj'esa .5. A2Elk/656.5} J3" w M ATTORNEYS.

United States Patent CORNER LOCK .BOX

Alfred B. Kieingers, Jr., Middletown, Ohio, assignor to The InterstateFolding Box Company, Middletown, Ohio, a corporation-f Ohio ApplicationDecember 15, 1955, Serial No. 553,234

9 Claims. (Cl. 229-31) My invention relates to paperboard boxes and moreparticularly to a novel corner lock construction for a collapsible boxwhereby the box may be quickly erected and automatically retained in theerected condition without the use of interlocks or other forms ofinterengaging means which require separate handling on the part of thebox user,

A principal object of my invention is the provision of a corner lock boxof the character described which is formed from a one-piece paperboardblank which may be conveniently folded and glued on standard box makingequipment.

A further object of my invention is the provision of a corner lock boxwhich employs a minimum amount of paperboard in its formation and whichmay be readily fabricated as an inexpensive article of manufacture.

Yet a further object of my invention is the provision of a one-piececollapsible box which may be readily erected by simply expanding anopposed pair of the body walls of the box, and which, upon erection,will be maintained in the erected condition by positively acting meanswhich lock the corners of the box in the erected condition. Yet theconstruction of the box is such that it may be readily collapsed forstorage.

Still a further object of my invention is the provision of a corner lockbox of the character described in which the positive engagement of thecorner locks is effected simply by the exertion of pressure against thewalls of the box, the corner locks snapping into locked position andremaining there until positive force is exerted in the oppositedirection to disengage them.

These as well as other objects of my invention which will appearhereinafter or which will be apparent to the skilled worker in the artupon reading these specifications, I accomplish by that construction andarrangement of parts of which I shall now describe an exemplaryembodiment.

Reference is now made to the drawings forming a part hereof and wherein:

Figure l is a plan view of a collapsible box blank formed in accordancewith my invention.

Figure 2 is a perspective view illustrating the blank of Figure l in theknocked-down or flat-folded condition.

Figure 3 is a perspective view similar to Figure 2 but illustrating thebox blank in a state of partial erection.

Figure 4 is a perspective view of the erected blank just prior to theengagement of the corner locks.

Figures 5 and 6 are partial perspective views illustrating the manner inwhich the corner locks are effected.-

Figure 7 is a perspective View similar to Figure 4 with the corner locksin the locked position.

In the practice of my invention, I provide a blank formed frompaperboard, boxboard or similar material "ice suitably cut and scored toprovide a main or bottom panel 1 to the side edges of which arearticulated opposed pairs of body walls 2, 3 and 4, 5. Corner connectingmembers join the end edges of adjacent body walls. The corner connectingmembers at the ends of body wall 2 comprise inner parts 6 and 7articulated to-the end edges of the wall 2 and outer or strap-formingportions 8 and 9 articulated at their outer ends to the outer corners ofthe inner parts along the diagonal score lines 10 and 11 and at theiropposite ends to the body walls 4 and 5 along thelines of articulation12 and 13 extending along the end edges of the body Walls 4 and 5. Linesof cut 14 and 15 separate the inner and outer parts from each other, andthe inner parts are additionally separated from the adjacent body walls4 and 5 by means of the lines of cut 16 and 17 which extend inwardlyalong the end edges of the body walls from the ends of the lines of cut14 and 15 to the corner edges of the main panel -1.

The body wall 3 is, in similar fashion, provided at its ends with innerportions 18 and 19, strap forming portions 20 and 21 connected to theinner portions by diagonal score lines 22 and 23 and to the body walls 4and 5 by lines of articulation 24 and 25. Lines of cut 26 and 27separate the inner and outer portions and lines of cut 28 and 29separate the inner portions from the adjacent body walls 4 and 5,respectively.

Elongated notches 30, 31, 32 and 33 are cut in each of the innerportions of the corner connecting members, and mating notches 34, 35,36, and 37 are provided in the ends of the body walls 2 and 3, in themanner illustrated.

In assembling the blank just described, the blank will be preferablymoved in the direction of the arrow A (Figure 1) whereupon adhesive willbe applied to the inner portions 6, 7, 18 and 19, as indicated by theshaded areas in Figure 1, whereupon the body walls 4 and 5 together withthe corner connecting members will be infolded so as to bring the blankto the condition illustrated in Figure 2. The infolding of the cornerconnecting members serves to bring the inner portions thereof intoadhesive engagement with the underlying portions of the body walls 2 and'3. Furthermore, it will be noted that upon the infolding of the cornerconnecting members, the mating notches, such as the notches 30, 33, willcoincide to define projecting tips 38, 39, 40 and 41 .at the outer.corners of the flat-folded blank. This is the knocked-down orflat-folded condition of the blank in which it may be shipped to thecarton user.

As seen in Figure 3, the knocked-down structure may be readily erectedby applying inwardly directed pressure to the body walls 2 and 3, asindicated by the arrows B. As the walls 2 and 3 fold inwardly andupwardly, the strap forming portions 8, 9 and 20, 21 cause the adjacentbody walls 4 and 5 to automatically erect themselves, the latter bodywalls and the strap forming portions separating along the lines of cutfrom the inner portions of the corner connecting members which areadhesively secured to the body walls 2 and 3. Upon erection of the bodywalls, the structure will assume the condition illustrated in Figure 4of the drawings. In the erected condition of the structure, it will benoted that the strap forming portions 8, 9 and 20, 21 will have beenreversely folded with respect to the inner portions 6, 7 and 18, 19along the diagonal score lines 10, 11 and 22, 23. In particular, it willbe noted that the projecting tips 38, 39, 40 and 41 project upwardlybeyond the lower edges of the strap forming portions and, in theinitially erected structure, lie to the outside of the strap formingportions. It is preferred that the projecting tips extend upwardlybeyond the lower edges of thestrap forming portions by a distance of 4;or 7 of an inch, although it will be obvious that the amount of overlapmay be varied without departing from the spirit and purpose of theinvention.

Subsequent to the erection of the structure to the condition best seenin Figure 5, i. e. with the projecting tips lying to the outside of thestrap forming portions, light pressure against the ends of the bodywalls 2 and 3 will cause the tips to snap into locking engagement inback of the straps, in the manner illustrated in Figure 6. The tips,once engaged in back of the straps, will act to lock the body walls inerected condition where they will remain until positive force is appliedagainst the inside of the walls 2 and 3 to disengage the tips. Myconstruction thus provides a simple and yet effective corner lockconstruction which does not require the manipulation of interlocks orthe like as is customary in boxes of this character. The erected andlocked box is seen in Figure 7 wherein a handle member is illustrated indotted lines, it being obvious that a handle element may be associatedwith the structure as an incident of its formation or may be associatedtherewith at a later time, as the conditions of use will dictate.

Modifications may be made in my invention Without depating from thespirit of it. For example, the nature of the invention is such that itmay be applied to boxes and cartons of various sizes and formed fromvarious weights of boxboard, and it will be understood that thedimensions of the strap forming portions and the projecting tips may bealtered accordingly, as is well within the skill of the worker in theart. Furthermore, it should be pointed out that the opposed pairs ofbody walls will comprise the side and end walls of the box, and wherethe terms side walls and end walls are employed in the claims whichfollow, it will be understood that the terms may be used interchangeablyand do not constitute limitations on my invention.

Having thus described my invention, what I desire to secure and protectby Letters Patent is:

1. In a corner lock box, a pair of adjacent body walls in edge abuttingrelation defining a corner of said box, a strap member hingedlyconnected to the upper portion of the abutting end edge of a first ofsaid body walls, said strap member extending along the inside of theother of said body walls and hingedly connected at its opposite end tosaid last named body wall along a hinge line spaced from the corner ofsaid box, a notch in said last named body wall intermediate the ends ofsaid strap member, said notch extending downwardly from the upper edgeof the said body wall to define an upwardly projecting tip, the lowerextremity of said notch lying below the lower edge of said strap memberwith said tip projecting upwardly beyond the lower edge of said strapmember to provide a locking means capable of engaging the inner surfaceof said strap member.

2. In a corner lock box, a pair of adjacent body walls in edge abuttingrelationship to define a corner of said box, a corner connecting memberjoining the abutting end edges of said body walls, said cornerconnecting member comprising a strap member hingedly connected to theupper portion of the end edge of a first of said body walls, said strapmember extending along the inside of the other of said body walls, andan inner portion articulated to the end edge of said last named bodywall, said inner portion being reversely folded and adhesively securedto the inner surface of the body walls to which it is connected, saidstrap member being hingedly connected at its opposite end to the outeredge of said inner portion, mating notches in said last named body walland said inner portion intermediate the ends of said strap member, saidmating notches extending downwardly from the upper edge of said bodywall to define an upwardly projecting tip, the lower extremity of saidmating notches lying below the lower edge of said strap member with saidtip projecting outwardly beyond the lower edges of said strap member toprovide a locking means capable of engaging the inner surface of saidstrap member.

3. In a corner lock box, a corner connecting member adjoining the endsof adjacent body walls of said box, said corner connecting membercomprising an inner part articulated to the end edge of a first of saidbody walls, said inner part being reversely folded and secured to theinner surface of the body wall to which it is articulated, and an outerstrap member hingedly connected at one end to the end edge of the otherof said body walls and at its opposite end to the free edge of saidinner part, and mating notches in said first named body wall and saidinner part intermediate the ends of said strap member, said notchesextending downwardly from the upper edge of said last named body wall todefine an upwardly projecting tip, the lower extremity of said matingnotches lying below the lower edge of said strap member with said tipprojecting upwardly beyond the lower edges of said strap to provide alocking means capable of engaging the inner surface of said strapmember.

4. In a corner construction for a collapsible box, first and second bodywalls defining a corner of said box, a strap member hingedly connectedat one end to the end edge of said first body Wall and hingedlyconnected at its opposite ends to said second body wall at a pointspaced from the end edge thereof, said strap member extending in generalparallelism to said second body wall, and strap engaging means formed insaid second body wall adjacent the ends thereof, said last named meanscomprising an upwardly projecting member having a point of origin belowthe lower edge of said strap member and extending upwardly beyond thelower edge of said strap member by a distance sufficient to permit it tobe passed from one side of said strap member to the other for abutingcontact therewith.

5- The corner construction claimed in claim 4 wherein an inner cornerconnecting part is connected to the end edge of said second body wall,said last named part lying in reversely folded condition and adhesivelysecured to the inner surface of said second body wall, with the end edgeof said strap member hingedly connected to the free corner edge of saidlast named part.

6. In a blank for forming a corner lock box, a pair of adjacent bodywalls, a corner connecting member joining the adjacent end edges of saidbody walls, said corner connecting member comprising an inner partarticulated to the end edge of a first of said body walls, and a strapmember articulated at one end to the end edge of the other of said bodywalls and at its other end to said inner part along a diagonal scoreline, said inner part being separated from said second body wall by aline of cut defining the end edge of said second body wall, and saidstrap member being separated from said inner part by a line of cutterminating at one end at said first named line of cut and at theopposite end at said diagonal score line, said inner part and said firstnamed side wall having mating notches therein adapted to define aprojecting tip adjacent the end of said first body wall.

7. In a knocked-down corner lock box wherein a pair of side walls arefolded inwardly and a pair of end walls are folded outwardly, cornerconnecting parts including strap-like members defined in said cornerconnecting parts by lines of severance, said strap-like mem- 5 ciaimedin claim 7 wherein said projecting tips are defined jointly in said endwalls and in the portions of the corner connecting parts adhesivelysecured thereto.

9. A corner construction for a corner lock box comprising a side walland an end wall interconnected by means of a corner connecting part,said corner connecting part being divided into a first portion which isinfolded and adhesively secured to the said end wall and a strap formingportion hingedly connected at one end to the side wall and hingedlyconnected at the other end to said first named portion along adiagonally disposed line of fold, said end wall and the first namedportion of said corner connecting part being cut away to define anupwardly projecting tip at the corner of said end wall, said tip beingadapted to be engaged in back of said strap-forming portion.

No references cited.

